Apparatus to indicate the stoppage of carriers in the transmission-tubes of pneumatic-despatch-tube systems.



J. P. SKIRROW. APPARATUS TO INDICATE THE STPPAGE 0I CARRIERS IN THE TRANSMISSION .TUBES 0I' PNBUMATIG DBSPATCH TUBE SYSTEMS.

Patented Feb-.17,1914

APPLICATION FILED 25, 1912.

v UNITED AsTATEs PATENT OFFICE.

JOHN F. SKIRROW, F EAST ORANGE, NEW JERSEY.

APPARATUS To INDICATE THE sTorPAGE or CARRIERS IN THE TnANsinssroN-Tuins:

or PNEUNATIc-nEsrAren-TUBE- SYSTEMS.

kSpecication'ot Letters Patent. I y Patented eb. 1.71,y l.

Application led January 1912.' Serial No. 673,472.

To all 'whom 'it may concern I Be it known that I, JOHN F. SxIRRoW, a citizen of the United States, and resident of the town of East Orange, county of Essex, and State of New Jersey, have invented certain new and useful Improvements in Apparatus to Indicate the Stoppage of Carriers' 1n the Transmission-Tubes of Pneumatic'- Despatch-Tube Systems, of which the following is a specication.

The object of this invention is to provide a simple and reliable means to indicate when a carrier has been stopped in the transmission tube ofa pneumatic despatch tube apparatus. Y

Another objectof the invention is to provide a pressure device near the exit end of the transmission tube, adapted to be operated by the air flowing outwardly through the tube in front of an approaching carrier and to connect said pressure device to a suitable signaling means at the transmission end of the tube so that the operator transmitting carriers will know whether or not said carriers are traveling through the transmission tube.

Another feature of the invention is to rovide means whereby upon the failure o air to move in its normal manner through the transmission tube near the exit end thereof, an electric signaling circuit will be co-mpleted, thereby giving warning to the operator at the sending end of the tube that a carrier, or some other matter, vhas sufliciently blocked the transmission tube to prevent or materially interfere with the flow of air therethrough.

Another object of the invention is to place the pressure device a suitable distance inwardly from the discharge end of the transmission tube, so that the pressure therein may be utilized to operate a signaling device. Another object of the invention is to provide pressure actuated means which, upon any material variation in the fiow of air through the transmission tube, will permit the contacts ot' an electric circuit to come together and thereby complete an alarm circuit. the alarm being at the transmitting end of the carrier tube.

This invention is particularly adapted for use on long lines of transmission tubes where it is diiicult to give notice to the transmission station when the carriers are blocked in the tube.

of -carriers become blocked in the tube.

In the operation of transmissiontubesof considerable length it heretofore has been found practically impossible to determine when `the carriers are blocked therein, with the result that frequently a large number It is then a difficult operation-to release them. By means of this invent-ion the stoppage of the first carrier will be immediately indicated to the operator at 'the transmission end of the tube and he will at once cease sending carriers until he stopped one is released and forwarded to the exit end of the tube. Y i

Any suitable form of pressure device may be employed and any suitable form of indicator or signal may be arranged to be operated by said pressure device.

In the drawings, Figure 1 is a diagrammatic view of a pneumatic tube system with the automat-ic alarm applied thereto; and Fig. 2 a detail sectional view of'the pressure device for opening and closing the' alarm circuit. l

Referring to the various parts by numerals, l designates a blower for supplying air under pressure to the transmission tube:I 2 a transmission head throughl which the carriers may be inserted into the transmission tube. Said head may be. of any suitable form. Connected .to this transmitting head and extending-to the receiving station is a transmission tube 3. The exit or discharge end of this tube is arranged to deliver carriers into a basket or other receptacle Ll.

At the pro-per distance from the discharge end of the tube I insert in the tube and in communication-with its interior, a pressure `de vice 5. This device, as shown, consists of a iet nozzle 6 arranged to direct a jet of air into a vibratory cup 7, said cup being mounted on a pivoted arm 8 and arranged opposite the exit end of the jet nozzle.

Any suitable form of signal means may be employed at the Ireceiving end of the tube, but I prefer to employ an electric bell, the circuit for said bell being connected to the vibratory arm carrying the cup, and to a front stop 9. The jet nozzle is in communication with the interior of the transmission tube and is located at such a distance from the discharge end thereof that the friction of the air on the sides of the tube and the atmospheric pressure at the open end of the tube will be sutlicient to create a pressure. in the tube so that, although the air is moving toward the em't end of the tube and is free to escape at said end there will still be sulhcient pressure in the tube to operate the alarm device. As shown in the drawings, the air in the tube will pass out through the jet nozzle and impinge within the cup carried b the vibratory arm. The

nozzle isprovide with an adjustable valve so that the amount of air escaping therefrom may be nicely regulated. Connected to the vibratory arm is a spring 1() which normally tends to throw the said arm against the electric contact 9 to complete the alarm circuit. When a carrier is traveling throughthe transmission tube the air from the jet nozzle will force the cup and its lever away from the contact 9, thereby breaking the alarm circuit and indicating to the operator that the carrier is passing properly through the tube.

In the operation of the apparatus, when carriers are blocked in the transmission tube between the jet nozzle and the transmission station, the flow of air through the transmission tube and beyond the blocked carrier will be'very small and the arm 8 is so adjusted that it will permit the spring 10 to swing it against the contact 9 upon a slight variation of the air jet from the jet nozzle. It is, therefore, manifest that when one carrier is blocked in the transmission many forms of pressure operated devices may be substituted for the jet nozzle shown and described herein, and I wish it to be distinctly understood that I am not to be restricted to the use of a jet nozzle in this form of apparatus for the purpose of holding open the Valarm circuit.

It is to be noted that the apparatus is designed to be operated by the air pressure in front of a carrier and at the discharge end of the line. The air in front of a traveling carrier operates the apparatus to hold merges@ the signal circuitl open, and upon the stoppage of said carrier within the tube the pressure in front of said carrier will be repleted.

This invention 1s particularly deslrable for use on lon transmission tubes where carriers are being constantly transmitted therethroughjin one direction in rapid succession, and where at times, a number of said carriers are in transit at the same time. It is manifest that in an apparatus of this type the operator at the transmitting end lor station of the tube should have instant notice of the stoppage of the carriers.

What I claim is: y

1. rlhe combination of a carrier transmitting tube, an alarm circuit, a signal in said circuit, means holding said circuit closed, and means located near the discharge end of the transmission tube and ada ted to be operated by the air pressure in ront of a moving carrier independently of the carrier propelling pressure, to hold the alarm circult open whereb should the carrier stop the alarm circuit will be closed..

duced and the alarm circuit will be comc 2. A pneumatic despatch tube provided with receiving and delivery terminals, means for supplying air under pressure to said tube to transmit carriers, an electric circuit including an alarm located adjacent the receiving terminal of the tube, a switch arm in the circuit near the discharge terminal, means acting on said switch to normally close the alarm circuit and a jet nozzle connected to the tube adjacent its delivery end and arranged tol deliver a jet of air upon the switch arm to hold the circuit open.

3. A pneumatic despatch tube provided with receiving and delivery terminals, means for supplying air under pressure to said tube to transmit carriers, an electric circuit including an alarm located adjacent the receiving terminal of the tube, a switch arm in the circuit near the discharge terminal, means acting on said switch to normally close the alarm circuit and air operated means attached to the tube adjacent its delivery end and operating upon the switch arm to hold the alarm circuit open.

In testimony whereof I hereunto affix my I'Vitnesses:l

A. J. EAVES, E. D. NOLLER. 

